I recently acquired quite a few teeth from the Saratov region of Russia. Melovatka Formation. I have a few that I can use some ID help with. I will work on getting better pics but for now this is what I have.
This is a formation from which Pseudomegachasma teeth were described and I believe I may have found 1-3 teeth that fit for that species. I spent a great deal of time under the scope with these teeth and comparing them to those described. I will eventually send pictures to Dr. Shimada when I have better quality pics. The teeth are all 4-5 mm.
The first tooth is the one that I am really secure in my ID but I am no expert.